1. Field
The present application relates to a tube for separating portion of a sample including a liquid, and methods for using a tube to separate a sample.
2. Discussion of Related Art
In some liquid sample processing techniques, it is desirable to separate agglomerated, clotted or otherwise formed clumps of material from liquid and other small components in the sample. For example, clotting may occur in a blood sample after its removal from the body, and it may be desirable to separate fibrin or platelet clots from other portions of the blood sample (such as serum), whether the clotting occurs naturally or artificially such as in response to a reagent added to the sample.
Various devices are known to separate clumps of material from liquid portions of a sample. For example, one type of a device, known as a serum separator, is used to mechanically separate serum or plasma from other portions of a blood sample. One example of a serum separator is shown in FIG. 1 and includes a blood collection tube 10 with a cylindrical filter member 12 disposed within the tube. A weight 14 is attached to the filter member 12 so that the filter member moves down the tube and through the sample during centrifuging. The filter member is made from a material having pores which permit the passage of the liquid phase of a blood sample, but prevents the passage of the insoluble solid blood phase portion 18. As the filter member 12 moves down the tube 10, the serum or plasma 16 is forced through the pores of the filter element while particulates remain below the filter element in the solid phase portion 18.